1. Field of the Invention
The present invention relates to a laminated electronic part and a method of producing the same.
Generally, production of laminated electronic parts such as laminated ceramic capacitors and so forth, includes sequentially printing plural internal electrodes on the surface of a mother ceramic green sheet, laminating a plurality of the mother ceramic green sheets, pressing the green sheets in close contact with each other to form a mother ceramic lamination-block, cutting the mother ceramic lamination block in conformation with the arrangement of the internal electrodes to produce respective laminated ceramic chips, firing the cut laminated ceramic chips, and forming external electrodes on the fired laminated ceramic chips.
For example, Japanese Unexamined Patent Application Publication No. 9-22830 describes a high yield method for producing capacitors of which the deviation of the static capacitance is small. According to this production method, an internal electrode is formed on the surface of a ceramic green sheet, and thereafter, the area is measured by an in-line system. The number of ceramic green sheets to be laminated is calculated so that a desired electrostatic capacitance can be obtained.
According to the above-mentioned method, the area of an internal electrode is measured, and the number of ceramic green sheets to be laminated is calculated based on the area data. However, the calculation is carried out assuming that the ceramic green sheets have a constant thickness. That is, it does not consider that the electro-static capacitance may change due to variations in the thickness of the ceramic green sheets.
A CCD camera or the like is used in measurement of the area of an internal electrode. Regarding conventional CCD cameras, the pixel shapes are rectangular, respectively, and the pixels are arranged in a rectangular grating pattern. Accordingly, problems are caused in that the resolutions in the longitudinal and transverse directions of the respective CCD cameras are different from each other, and the measurement precision is low.